Vitamin B-17 is an alternate name for apricot kernel or laetrile, the inner seed of the apricot fruit, an ingredient in the production of chemicals for pharmaceutical purposes, states WebMD. Its most common use is to treat cancer. Individuals take apricot kernel by mouth or receive it as an injection.
Apricot kernel contains amygdalin, a toxic chemical. The body converts this to cyanide, which is poisonous, notes WebMD. When researchers began using this treatment, they expected the cyanide to damage or shrink tumors, thus treating the cancer. As of 2015, research has revealed that the amygdalin actually converts to cyanide in the stomach. It then spreads throughout the body and causes severe damage or death in some instances.